Driving after consuming alcohol continues to be a major public health problem, particularly for young adults, who report the highest rates of drinking and driving. Although changes in policy (minimum legal drinking age; per se laws) have been successful in reducing drinking and driving, individual difference factors predispose certain people to drive after drinking. Research clearly demonstrates that impulsivity is one such individual difference factor. However, to date the influence of impulsivity on drinking and driving has primarily been examined using questionnaire measures of impulsive personality traits. No previous study has examined individual differences in acute alcohol effects on behavioral measures of impulsivity and their association with drinking and driving behavior. The proposed project will test a model of drinking and driving as influenced by the acute effect of alcohol on two impulsivity constructs: behavioral inhibition (i.e., the ability to inhibit/suppress behavior) and impulsive decision making (i.e., the ability to make decisions in accordance with time and probability contingencies). Participants will be drawn from an ongoing longitudinal study (PI: Kenneth Sher, R37 AA07231) based on the longitudinal course of their drinking and driving behavior. All participants will complete multiple behavioral measures of impulsivity in two laboratory sessions (alcohol, no beverage control), as well as a 3 month follow-up assessment of their drinking and driving behavior and risk variables specific to drinking and driving. The proposed project has three specific aims: 1) Test the association of sober and intoxicated impulsivity with engagement in and persistence of drinking and driving. 2) Test how the effect of alcohol on impulsivity is moderated by other risk factors for alcohol use. 3) Test the interaction between impulsivity and risk factors specific to drinking and driving in determining drinking and driving behavior. Results of the proposed project can advance drinking and driving theory, research, and intervention by delineating the role of intoxicated impulsivity in drinking and driving decisions.